The investigation carried out in this research work concerns the effect of the addition of H-2 on performance and emission characteristics of a single cylinder, 4-stroke diesel engine. The tests were performed using diesel as a pilot fuel, with hydrogen addition at varying load condition using a Timed Manifold Injection (TMI) system has been developed using ECU (electronic control unit) with varying injection strategy to deliver hydrogen on to the intake manifold. The results showed a significant increase in BTE with appreciable decrease in BSEC of the engine when compared to conventional diesel-fueled operation. The emission of CO2 and NOx was found to increase with enhancement of H-2 addition. The emission of UHC was found to be very high at low load conditions, but it enhanced as the load increased for all hydrogen injection while Soot emissions decreased. Thus, this paper provided a potential to investigate the effect of the addition of H-2 on the performance and emission characteristics of a diesel engine and how to get a best ratio of H-2 addition. The tradeoff study also consolidated the verity that Diesel H-2 dual fuel operation was instrumental in resolving the high performance low emission paradox. (C) 2015 Elsevier Ltd. All rights reserved.